\documentclass[12pt]{article}
\usepackage{tikz}
\usetikzlibrary{decorations.markings}
\usetikzlibrary{calc,fadings,decorations.pathreplacing}
%% helper macros
\usepackage[cp1251]{inputenc}
\usepackage{cmap} % для корректной генерации русского текста в PDF
\usepackage{mathtext} % русские буквы в формулах
\usepackage[T2A]{fontenc}
\usepackage[russian]{babel}
\usepackage{amssymb}
\usepackage{amsmath}
\usepackage{graphicx}
\usepackage{indentfirst} % отступ первого абзаца
\usepackage{calc}
\usepackage{icomma} % правильная десятичная запятая
\usepackage{geometry}
\usetikzlibrary{snakes}
\usetikzlibrary{patterns}
\usetikzlibrary {calc} 
%\geometry{papersize={ 20 cm, 14 cm }}
\geometry{left=0cm}
%\geometry{right=0cm}
\geometry{top=-0cm}
\geometry{bottom=0.1cm}
\tikzstyle{spring}=[line width=0.8,blue!7!black!80,snake=coil,segment amplitude=5,segment length=5,line cap=round]

%\def\textto{Лист необходимо сдать вместе со своими решениями!}
\begin{document}

\begin{tikzpicture}
%\draw (10, 12.5) node{\textto};
\coordinate (B) at (9, 8);
\coordinate (C) at (8.5, 6.7);
\coordinate (BB) at (16, 4.5);
\coordinate (Alpha) at (5, 0);
\coordinate (L) at (intersection of B--C and BB--Alpha);
\draw (B) -- (C);
\draw[fill] (B) circle(0.05 cm) node[left]{$B$};
\draw[fill] (C) circle(0.05 cm) node[left]{$A$};
\draw[fill] (BB) circle(0.05 cm) node[below]{$B'$};
\draw (Alpha) -- ($(Alpha)!1.3!(BB)$) node[below]{$\alpha$};

%Задание углов плоскости рисования
\draw[draw = none] (0, 0) circle(0.1 cm);
\draw[draw = none] (0, 13) circle(0.1 cm);
\draw[draw = none] (19, 0) circle(0.1 cm);
\draw[draw = none] (19, 13) circle(0.1 cm);
\end{tikzpicture}

\rule{0cm}{0.5cm}

\begin{tikzpicture}
%\draw (10, -0.5) node{\textto};
\coordinate (B) at (9, 8);
\coordinate (C) at (8.5, 6.7);
\coordinate (BB) at (16, 4.5);
\coordinate (Alpha) at (5, 0);
\coordinate (L) at (intersection of B--C and BB--Alpha);
\draw (B) -- (C);
\draw[fill] (B) circle(0.05 cm) node[left]{$B$};
\draw[fill] (C) circle(0.05 cm) node[left]{$A$};
\draw[fill] (BB) circle(0.05 cm) node[below]{$B'$};
\draw (Alpha) -- ($(Alpha)!1.3!(BB)$) node[below]{$\alpha$};

%Задание углов плоскости рисования
\draw[draw = none] (0, 0) circle(0.1 cm);
\draw[draw = none] (0, 13) circle(0.1 cm);
\draw[draw = none] (19, 0) circle(0.1 cm);
\draw[draw = none] (19, 13) circle(0.1 cm);
\end{tikzpicture}


\end{document}